Wood-screw.



A. J. GEHRING.

WOOD SCREW. APPLICATION FILED r2842, 1916.

1,1 84,173. Patented May 23; 1916.

III/1; J g e J I W GUM-nag:

vwawboz ADAM J. GEHRING, OF GAR'DENVILLE, MARYLAND.

WOOD-SCREW.

Specification of Letters Patent.

Patented May 23, 1916.

Application filed February 12, 1916. Serial No. 77,944.

To all whom it may concern:

Be it known that I, ADAM J. Genuine, a citizen of the United States, resldmg at Gardenville, in the county of Baltimore and State of Maryland, have invented certain new and useful Improvements in Wood- Screws; and I do declare the followmg to be a full, clear, and exact description of the invention, such as will enable others skllled in the art to which it appertains to make and use the same.

My invention relates to improvements 1n wood screws and has for one object to provide a device of this class which when driven will present an entirely flat surface w thout any cavities or incisions in which d1rt or other matter may lodge, the ap earance being therefore much more sight y than that" of the usual type of screw employing a transverse kerf.

Another object of the invention is to form the screw head with a pair of parallel bores to receive projecting lus on a screw drlver when driving or removing the screw, and to so locate and form said bores as to allow them to also receive a pair of locking pins to be used for preventing rotation of the screw after the latter is driven, said bores being also solocated as to allow these plus to be driven therefrom into the work when the screw is to be removed.

With the foregoing objects in view, the invention consists of certain novel features of construction and unique combinations of parts to be hereinafter fully described and claimed, the descriptive matter being supplemented by the accompanying draw ng which constitutes a part of this application and in which:

Figure 1 is a side elevation of a screw constructed in accordance with the invention,

showing the same locked inoperative position; Fig. 2 is a similar vlew with parts broken away and in section; Fig. 3 1s an end elevation of the'screw applied; Fig.4,

is a view similar to Fig. 1 showing the looking pins driven from the bores to allow the screw to be removed; Fig. 5 is a side elevation partly in' section showing the manner in which the improved screw is locked against rotation when passing'through a metallic plate; Fig. 6 is a fragmentary plan view of sucha plate; and Flg. 7 is a sectional view thereof taken on. the plane of the line 7- 7 of Fig. 6.

In Figs. 1 to 4 of the drawings, the numeral 1 designates an externally threaded screw shank equipped with the usual frusto cone-shaped head 2 having a flat outer end, the inner end of this head being preferably serrated as shown at 3 in order that it may serve as a file to form a countersink in the wood or the like W into which the screw is driven.

Formed longitudinally through the head 2 and opening through the inner and outer ends thereof, are two bores 4 of equal diameter throughout their lengths, the innermost sides of these bores being flush with the exterior of the shank 1 as depicted most clearly in Fig. 2. When driving the screw, a pair I of projecting pins on a suitable screw driver will be received in the bores 1 "to serve as rotating means for the screw, but after the latter has been driven, the bores in question are adapted to receive therein a pair of looking pins 5 of equal diameter throughout their lengths. The pins 5 are of a size to completely fill the bores 4 and are provided with flat outer ends which lie flush with the flat outerend of the head 2, thus presenting no shoulders or' the like against which matter of anykind might accumulate. The inner ends of the pins 5 project beyond the head 2 into the work as clearly shown in Fig. 2, these ends being preferably pointed as shown. Thus, the pins in question will readily prevent rotation of the screw.

In order to allow the screw to be withdrawn when desired, the pins 5 will be driven entirely through the bores 4 as shown in Fig. 4, this being done by the projecting pins on the screw driver above referred to .or by the use of a suitable punch. The

screw may now be rotated in the necessary covered-from the screw hole, these pins remaining intact and therefore being fit for further use.

In Figs. 5, 6 and 7 a screw 1 is shown identical in construction with that above described with the exception that its head is formed with no serrations, this type of screw being adapted for fastening a metal plate or the like P to another body such as that indicated at B. When this is to be done, the plate P will be formed with a counter-sunk opening 10 and will have an arcuate series of notches 11 opening into such opening. By the means above described, the screw will now be driven throughthe opening 10 into the body B and the'head of said screw will be received in the opening in question. Pins as will now be driven through the bores of the screw head and through the notches 11 into said body B. Obviously, this'arrangement will prevent rotation and removal of the screw until the pins are driven beyond the bores of 'thescrew head in hereinbefore'set forth. I

From the foregoing, it' will be understood that although the improved screw is of extremely simple and inexpensive formation, it will be highly, efiicient and durable' I am aware that screws have heretofore been used having heads with bores extending therefrom, but in so far as I am advised, the

exact arrangement of these bores shown in the accompa'nymg drawlngs has not heretofore existed. This-arrangeme-nt possesses advantages over the previous state of the art with which Lamfainiliar in that said bores serve asmeansfOrreceiVing a screw driver to drive or remove the screw, as means for receiving locking pins and for allowing said pins to be easily driven therefrom, and lastly for allowing these pins to be recovered.

a1 wi llwbe noted" that my improved screw furtheradvantage over the. ordinary screw' 'with thescrew driver notch in that such old style screws when used in the floor are quickly-"worn-down so that the screw driver notch'i's entirely worn away and in such case it is almost imposslble to remove the screw without mutilatlng the floor.

With respect to the screw describedvherein,

it will be seenthat the wrench and pin rece iving apertures 4 are extremely deep so that the head will never be worn suificiently to preventthe application of the screw drlver or wrench used to remove the screw.

1. A wood screw comprising a threaded shank having a circular head with a flat outer end, said headbeing formed with'a pair of cylindrical bores of equal diameter throughout their lengths lying parallel to the axis of the shank and opening through the inner and outer ends of said head, the innermost sides of the bores lying flushwith the manner throughout their lengths lying parallel to the axis'of the shank and opening through the inner and outer ends of said head, the innermost sides ofthe bores lying flush with the exterior of the shank, said bores being adapted to receive a pair ofprojecting pins on a screw driver for driving or removing the screw;- in combination with a pair of cylindrical pins of equal diameter throughout their lengths to be driven into said bores and to project beyond the inner ends thereof to lock' the screw against movement after being driven, said pins being also adapted to be driven entirely through said bores when thescrew is to be removed.

3. A wood screw comprising a threaded shank having a circular head with a fiat outer end, said head being formed with a pair of cylindrical bores of equal diameter throughout their lengths lying parallel to r the axis of the shank and opening through the inner and outer ends of said head, the innermost sides of the bores lying flush with the exterior of the shank, said bores beingadapted to receive a pair of projecting pins on a screw drlver for drlvmg or removing the screw; in combination with a metallic plate having a countersunk opening to receive the head of the screw and having bores to allow rotation of the screw.

In testimony. whereof I have hereunto 'set my hand in presence of two subscribing witnesses.

' 'ADAM J. GEHRING.

Witnesses:

. Josrgr'n B; Loruznvz, MICHAEL CHAYVT. 

